This is my KJW M700 that has been my little project for a year. From original I first upgraded it with better hop up and barrel. After that tapped to CO2 using Tanaka Long mag. Co2 and Gas wasn't very good choices but now I'm using HPA and getting chronoing results that varies +-1m/s when gun is shooting 150-160m/s. 160-170m/s variation is around 3m/s. Here is link to proof this.
And of course my gun is painted using Krylon OD, Light green and dark brown by tapping colors with sponge.
Some pictures:
https://www.flickr.com/photos/124508315@N02/14355738538/in/set-72157645445453155